Electric switch.



E. R. HIRST.

, ELECTRIC SWITCH.

APPLICATION IILED IEB.15, 190.9.A

Patented Aug.2,191o.

, UNTTED STATES PATENT oFFioE;

HARRY R. HIRST, F NEW BEDFORD, MASSACHUSETTS, ASSIGNOR TQ CHARLES KNOWLE, 0F NEW BEDFGRD, MASSACHUSETTS.

' ELECTRIC SWITCH.

'Specification of Letters Patent.

Patented Aug. 2, 1910.

.application filed February 15, 1909. Serial No. 477,905.

To all 'whom 'it may concern.'

'Be it known that I, HARRY R. HIRsT, of

vNew Bedford, in the county of Bristol and State of Massachusetts, have invented a new and useful Electric-Switch, of which the following is aspeciicati0n.

My invention relates to electric switches,`

and my object is to provide a switch which will have the important advantage of a snap make and break, and'which will also be very compact inr construction and efficient in op eration. Y Myinvention consists mainly-1n the combinations hereinafter described and claimed,

and especially in the combination in whichv the pivot of`v `the rock arm is between the ends of the spring.

In the drawings Figure 1 is an elevation of a switch embodying my invention, the

front wall of the casing being removed; Fig.

2 is a central vertical section of said switch;`

and 3 is a bottom plan of said switch.

Casing A is of insulating material, such,

as porcelain. Within the casing are the binding posts D and D,.,and the contact terminals E and E.

on the foot of the binding post and at its opposite end has a contact portion e. The terminals and binding posts are held in position by screws d and al. The upper ends of the binding posts carry the binding screws d2 and d. Plate F has screw holes f f by which 'it may be attached to the casing and has also apertures ff f `by which with the aid of screws or otherwise the casing and switch may be screwed to a wall or partition.YV

late F are fas- Gr in which I To the under side-of the tened the bearing plates lpivotally secure lever H which is composed are connected to each other by pin b and at their ends are pivotally connected to the push-buttons M and M. The rock arms Each Contact terminal has a right-angled foot portion resting f swings on its pivot `and carries pin b over toward a line from pin b to pivot 7c. This movement stores power in the s ring by increasing the tension until pin passes the line above referred to and then the power stored in the spring is free. to act and does act' to give a rapid movement to the lever and consequently a snap make and breakv of the terminals b* b4, this operation-being in reality the storing of power by the Inovement of the spring -until the moment when it is desired to move the lever, and then ,at that moment utilizing the power at its maximum.

It is to be noted as an important advantage of the preferred form of my switch that I use the space between thelevels of the lower and upper ends ofthe spring for the movement of the rock arm and lever with the result that my switch is -much more compact than heretofore, and it is to be observed that in the form of switch shown the length of the spring practically determines the depth of the switch because the pivots of the rock arm and lever are between the ends of the spring. With this arrangement I may' have a very short throw for the lever which is conducive to the general compactness of thel switch, it being the fact Vthat the less depth the switch has the more desirable it is. It isnlso to be noted that in the forni shown- 4the lever and rock arms have the same pivot which allows me make a very -scribed comprising a pivoted rock arm; a

ioo

pivoted lever; a spring connectingl the rock arm and lever; and a single stop which limits the movements in both directions of both the rock arm and lever.

2. An electric switch of the 'character de-4 scribed comprising a pivoted rock arm 5 a.v

pivoted lever; a tension spring connecting' the rock arm and lever, the pivot of the rock Iarm being between the ends of the spring;

and asingle stop Which limits the movesingle stop mounted in said bearing to enments in both directions of both the rock gage said .projections and one end of said arm and lever. lever to limit the movement in both direc- 3. An electric switch of the character cletions of both the rock arm and lever; and 5 scriloed comprisilg ah buring; adllivoted push buttons connected with the rock erm. 1 5

roc arm mounte int e caring an avng s, projections; a lever pivoted in said bearing HARRY R' HIR near its middle, the pivots of the rock arm Witnesses: and lever being co-incdent; a tension spring WM; H. HAND, J r., 1o connectingthe rock arm with said lever; a JAMES BROWN. 

